JCT The CICS log manager does not support journal data sets, making the journal control table obsolete. The CICS system log and journals are mapped to MVS system logger log streams (or, for some journals, SMF data sets) by means of JOURNALMODEL resource definitions.

JSTATUS CICS log manager does not support journal data sets, on either disk or tape, making this initialization parameter obsolete.

PLI removed because DOS PL/I is not supported.

SCS removed because the storage cushion size is determined by CICS.

System initialization modifications (SIMODs) are obsolete.

START the INITIAL option is added to indicate that CICS is to initialize as if this is a first-time start of the CICS region. Unlike a normal cold start, the cold start resulting from START=INITIAL causes CICS to purge the system log as well as the catalog data sets. An INITIAL start is the same as if you start CICS with a new system and newly defined catalog data sets.

TLT is replaced by the CSD function.

TRACE is replaced by new trace parameters.

TSMGSET there is no need for dynamic storage for temporary storage pointers as a result of the restructure of the temporary storage domain.

ZCP is not modifiable, thus the parameter is removed.

Note: CICS/ESA provides a default source (DFHSIT$$) with which you may start or use the default load module (DFHSIT) and override the defaults.

6.1.7 CSD and RDO Considerations

Below are commonly identifiable changes required to migrate a CICS/VSE system to CICS TS CSD and online resource definition entries. These parameters listed below should be viewed as a reminder of items to consider, and not as an inclusive list of parameter changes and/or obsolescence. You should review the CICS Resource Definition Guide, SC33-1684 for full details of parameters required for the different online resource definitions.

6.1.7.1 CSD

To start with the CSD is mandatory in CICS/MVS, but does not require an entry in the FCT.

You should define and initialize the CSD from the CICS/ESA system, as opposed to attempting to upgrade the CICS/VSE CSD to CICS/ESA. The reason is you want the space allocation of your CSD to accommodate the addition of VSAM FCT and DCT entries plus entries for comment fields (that is, entries not available to CICS/VSE). After the CSD is defined and initialized on the CICS/MVS system, you can use the DFHCSDUP utility to EXTRACT your user definition from CICS/VSE, then import it to CICS/MVS′s CSD. For details on using DFHCSDUP refer to your CICS Resource Definition Online and CICS Customization Guide.

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IBM OS/390 manual CSD and RDO Considerations, 7.1 CSD, System initialization modifications SIMODs are obsolete
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OS/390 specifications

IBM OS/390, a versatile operating system, was a cornerstone in enterprise environments and played a pivotal role in mainframe computing. Released in the mid-1990s, OS/390 combined the strengths of IBM's MVS (Multiple Virtual Storage) with new features and enhancements, targeting scalability, reliability, and performance in demanding business applications.

One of the key features of OS/390 was its robust support for multiple users and processes. The system allowed thousands of concurrent users to access applications and data, ensuring high availability and minimizing downtime—a critical requirement for many large organizations. This scalability was supported through various enhancements in memory management and processor scheduling, enabling optimal resource allocation across diverse workloads.

OS/390 was known for its superior workload management capabilities. The Workload Manager (WLM) component allowed administrators to define service policies, specifying how system resources would be allocated according to the priority of tasks. This ensured that critical business processes received the necessary resources while less critical tasks were managed more flexibly.

Another significant characteristic of OS/390 was its commitment to security. The operating system provided comprehensive security features, including user authentication, data encryption, and auditing capabilities. This focus on security was vital for organizations handling sensitive data, ensuring compliance with regulations and safeguarding against unauthorized access.

OS/390 also supported advanced technologies that facilitated integration and development. The system included features like the IBM CICS (Customer Information Control System) for transaction processing and IMS (Information Management System) for database management. These technologies allowed organizations to build robust, high-performance applications tailored to specific business needs.

The ease of network integration was another strength of OS/390. With the advent of the Internet and global connectivity, OS/390 systems could easily interface with various network protocols, enabling businesses to operate in a connected world. This inclusion paved the way for many organizations to expand their capabilities and offer new services, driving digital transformation.

In conclusion, IBM OS/390 represented a significant advancement in mainframe technology, combining scalability, security, and robust workload management. Its rich feature set and support for critical enterprise applications solidified its role as a vital component of many organizations' IT infrastructures, ensuring they could meet their operational challenges head-on while supporting future growth. As technology continues to evolve, the legacy of OS/390 remains influential in the realm of computing.
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